A conventional keyboard device for an electronic musical instrument is shown in FIG. 9. That keyboard device comprises a key b supported at its rear end for swinging movement about a shaft a mounted on a keyboard chassis, a hammer c disposed for swinging movement about a shaft a' so that it may be operated in association with key b during depression of the key, and a resilient member d resiliently engaged with key b at one end and with hammer c at the other end thereof and arranged to urge key b and hammer c respectively against the corresponding shafts.
The resilient member d of the keyboard device biases key b and hammer c in a swinging direction opposite to a direction of swinging movement occurring during depression of the key, i.e., in a returning direction.
The conventional keyboard device of FIG. 9 is disadvantageous in that the load characteristic, particularly the initial load on the key b, may be influenced by a dispersion in characteristic of the resilient member d, and in that it is difficult to provide a desired performance.